1. Field of the Invention
The present invention relates generally to ophthalmic lens storage containers each having a lens storage portion for storing an ophthalmic lens such as a contact lens, more particularly to such an ophthalmic lens storage container having a novel structure to facilitate removal of the ophthalmic lens from the lens storage portion.
2. Description of the Related Art
A blister package is known as one type of a container for storing a contact lens. JP-A-7-322911, JP-A-9-23916, JP-A-10-313928 and U.S. Pat. No. 6,050,398 disclose known examples of the blister package that includes: a package body having a generally semi-spherical cavity and a flange extending radially outward around the periphery of the cavity; and a cover sheet formed of a plastic film, aluminum foil or the like. The cavity contains the contact lens and a preserving solution, and the cover sheet is stripably sealed to the flange in a sealing zone that extends around the periphery of the cavity, to thereby enclose the cavity.
The conventional blister package constructed as described above may suffer from a problem that the sealing zone formed in the flange of the package body is roughed once the cover sheet is stripped or peeled from the flange, being likely to cause undesirable generation of burrs or fuzz on the sealing zone extending around the periphery of the cavity. Generally, a user removes the lens from the cavity by sliding the lens up along the bottom surface and the open-end peripheral surface in this order, while pushing or gripping the lens by his or her fingers. Accordingly, the contact lens may come into contact with the burrs left on the sealing zone, and is likely to be damaged, e.g., occurrence of flaws or cracks on the surface of the lens, by the contact with the burrs. Especially, a contact lens of disposable type, which has relatively thin wall thickness and a low strength, is more likely to be damaged by the contact with the burrs, upon the removal of the lens from the lens storage container.